I would have to say "the most careful". You can't say "the carefullest".
more careful, most careful
more careful, most careful
"Studying" is not a superlative, as it is not an adjective. "Most studious" is a superlative of "studious."
What is the comparative and superlative of Often
Superlative the silly
Comparative: More caring Superlative: Most caring
more careful, most careful
More careful, most careful
more careful, most careful
more careful, most careful
more cautious and most cautious
Sleep is a noun and does not have a superlative. Sleepy is an adjective and the superlative is "sleepiest."
The superlative for willing would be "most willing." There is no one-word superlative.
"Studying" is not a superlative, as it is not an adjective. "Most studious" is a superlative of "studious."
"Bib" is a noun and, as such, does not have a superlative form.
Tallest is the superlative.
superlative of quiet